单项选择题 AsystemadministratorneedstospecifyasetofFQDNtoIPaddressmappingsforalegacyserver；theadministratordoesnotwantthelegacyservertobereferencedbyotherservers.Which ofthefollowingshouldtheadministratorusetosetthis？（）

单项选择题 An administrator is troubleshooting a problem on an application server, but has not determined the cause of the problem and is not able to replicate the problem. Which of the following should the administrator do prior to escalating the issue?（）

单项选择题 Severalremotesalesemployees，whohavecomeintotheofficethisweek，reportthattheyare unabletogetontheInternet，butnootherusershavereportedsimilarissues.Thehelp deskhasescalatedtheissueandthecasenotesstatethattheusershaveIPaddressesthatbeginwith169.WhichofthefollowingshouldthesystemadministratorcheckFIRST？（）